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Yb for producing 
Lu with high radionuclide purity by Yb(
)LuNagai, Yasuki*; Kawabata, Masako*; Hashimoto, Shintaro; Tsukada, Kazuaki; Hashimoto, Kazuyuki*; Motoishi, Shoji*; Saeki, Hideya*; Motomura, Arata*; Minato, Futoshi; Ito, Masatoshi*
Journal of the Physical Society of Japan, 91(4), p.044201_1 - 044201_10, 2022/04
Times Cited Count：4 Percentile：40.77(Physics, Multidisciplinary)Recently, Lu is considered as one of the most important medical RIs for treating neuroendocrine tumors. A plan to produce Lu with high purity by using enriched Yb samples with irradiation of deuteron beams in accelerators has been discussed. However, since the other Yb isotopes contained in the Yb sample interacts with deuterons, Lu isotopes other than Lu are produced as impurities. Since the purity of Lu is important for medical use, a method to evaluate the impurity of Lu has been required. In this study, we proposed a new method to estimate production yields of each Lu isotopes in Yb samples with arbitrary isotopic compositions by using excitation functions of Yb()Lu reactions and the particle transport calculation code PHITS. The method plays an important role in discussing the isotopic composition of enriched samples to produce high-purity Lu using accelerators.
Cu and 
Cu via the Zn(n, p)Cu and 
Zn(n, np/d)Cu reactions using accelerator neutronsKawabata, Masako*; Motoishi, Shoji*; Ota, Akio*; Motomura, Arata*; Saeki, Hideya*; Tsukada, Kazuaki; Hashimoto, Shintaro; Iwamoto, Nobuyuki; Nagai, Yasuki*; Hashimoto, Kazuyuki*
Journal of Radioanalytical and Nuclear Chemistry, 330(3), p.913 - 922, 2021/12
Times Cited Count：8 Percentile：69.17(Chemistry, Analytical)Both Cu and Cu are promising radionuclides in nuclear medicine. Production yields of these radionuclides were quantified by irradiating 55.4 g of natural zinc with accelerator neutrons. Clinically suitable Cu and Cu yields were estimated by experimental based numerical simulations using 100 g of enriched Zn and Zn, respectively, and elevated neutron fluxes from 40 MeV, 2 mA deuterons. A combined thermal- and resin-separation method was developed to isolate Cu and Cu from zinc, resulting in 73% separation efficiency and 97% zinc recovery. Such methods can provide large scale production of Cu and Cu for clinical applications.
ZnO using polyethylene by accelerator neutronsTsukada, Kazuaki; Nagai, Yasuki*; Hashimoto, Shintaro; Minato, Futoshi; Kawabata, Masako*; Hatsukawa, Yuichi*; Hashimoto, Kazuyuki*; Watanabe, Satoshi*; Saeki, Hideya*; Motoishi, Shoji*
Journal of the Physical Society of Japan, 89(3), p.034201_1 - 034201_7, 2020/03
Times Cited Count：2 Percentile：18.41(Physics, Multidisciplinary)We found anomalously large yields of Ga, 
Ga, 
Zn and Cu by neutron irradiation on a ZnO sample in a polyethylene shield. Neutron beams are generated from the 
Be(
) reaction for 50 MeV deuterons. The yields obtained were more than 20 times larger than those in the unshielded sample. On the other hand, the yields of Ga, Ga, Zn and Cu from a metallic Zn sample and the yields of Cu, 
Ni and Zn from the ZnO and Zn samples were almost insensitive to the shield conditions. This finding would provide us a unique capability of accelerator neutrons to simultaneously produce a large amount of several radioisotopes, including proton induced reaction products, by using a single sample. The experimental data were compared with the yields estimated by using the Particle and Heavy Ion Transport code System and the result was discussed.
Hatsukawa, Yuichi*; Hayakawa, Takehito*; Tsukada, Kazuaki; Hashimoto, Kazuyuki*; Sato, Tetsuya; Asai, Masato; Toyoshima, Atsushi; Tanimori, Toru*; Sonoda, Shinya*; Kabuki, Shigeto*; et al.
PLOS ONE (Internet), 13(12), p.e0208909_1 - e0208909_12, 2018/12
Times Cited Count：3 Percentile：26.28(Multidisciplinary Sciences)Imaging of 
Tc radioisotope was conducted using an electron tracking-Compton camera (ETCC). Tc emits 204, 582, and 835 keV 
rays, and was produced in the 
Mo(p,n)Tc reaction with a Mo-enriched target. The recycling of the Mo-enriched molybdenum trioxide was investigated, and the recycled yield of Mo was achieved to be 70% - 90%. The images were obtained with each of the three rays. Results showed that the spatial resolution increases with increasing -ray energy, and suggested that the ETCC with high-energy -ray emitters such as Tc is useful for the medical imaging of deep tissue and organs in the human body.
Mo yield using large sample mass of MoO
for sustainable production of MoTsukada, Kazuaki; Nagai, Yasuki*; Hashimoto, Kazuyuki*; Kawabata, Masako*; Minato, Futoshi; Saeki, Hideya*; Motoishi, Shoji*; Ito, Masatoshi*
Journal of the Physical Society of Japan, 87(4), p.043201_1 - 043201_5, 2018/04
Times Cited Count：10 Percentile：56.82(Physics, Multidisciplinary)
Li ion beamsNishinaka, Ichiro*; Yokoyama, Akihiko*; Washiyama, Koshin*; Makii, Hiroyuki; Hashimoto, Kazuyuki*
Journal of Radioanalytical and Nuclear Chemistry, 314(3), p.1947 - 1965, 2017/12
Times Cited Count：2 Percentile：17.75(Chemistry, Analytical)Production cross sections of iodine, tellurium and antimony radionuclides in the 24-59 MeV Li + 
Sn reaction have been measured by the conventional stacked foil technique with -ray spectrometry. Excitation functions of the production cross sections were compared with a statistical model calculation. The contributions of complete and incomplete fusion in the production of observed radionuclides are discussed from the view points of production routes in the nuclide chart and decays for iodine, tellurium and antimony nuclides. The integral yields of 
I were deduced from the calculated excitation functions in the Li induced reactions on Sn isotopes in view of the production of medically important 
I. The results are discussed by comparing with literature values in the other reactions.
Cu produced by Zn(
)Cu to biodistribution study in tumor-bearing miceSugo, Yumi*; Hashimoto, Kazuyuki*; Kawabata, Masako*; Saeki, Hideya*; Sato, Shunichi*; Tsukada, Kazuaki; Nagai, Yasuki*
Journal of the Physical Society of Japan, 86(2), p.023201_1 - 023201_3, 2017/02
Times Cited Count：15 Percentile：67.00(Physics, Multidisciplinary)Cu produced by the Zn()Cu reaction was used for the first time to determine the biodistribution of CuCl
in colorectal tumor-bearing mice. High uptake of Cu was observed in the tumor as well as in the liver and kidney which are the major organs for copper metabolism. The result showing Cu accumulation in the tumor suggests that CuCl can be a potential radionuclide agent for cancer radiotherapy. It would also encourage further studies on the therapeutic effect in small animals using an increased dose of Cu produced by the Zn()Cu reaction using intense neutrons available at present.
Li + Pb reactionNishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Maeda, Eita*; Watanabe, Shigeki; Hashimoto, Kazuyuki; Ishioka, Noriko; Makii, Hiroyuki; Toyoshima, Atsushi; Yamada, Norihiro*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 304(3), p.1077 - 1083, 2015/06
Times Cited Count：10 Percentile：61.22(Chemistry, Analytical)Production cross sections of astatine isotopes 
At in the 29-57 MeV Li induced reaction with Pb target have been measured by 
- and -ray spectrometry. Excitation functions of production cross sections have been compared with a statistical model calculation to study the reaction mechanism of Li + Pb. Considerably small experimental cross sections of 
At and 
At compared with the calculation were clearly observed at incident energies higher than 44 MeV, indicating that the effects of breakup reaction play a role. A chemical separation of astatine from an irradiated lead target has been studied with a dry-distillation method. A complementary way to produce astatine isotopes has been developed.
Tc-radiopharmaceuticals obtained from Mo produced by 
Mo(n,2n)Mo and fission of 
UHashimoto, Kazuyuki; Nagai, Yasuki; Kawabata, Masako; Sato, Nozomi*; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji*; Ota, Masayuki; Konno, Chikara; Ochiai, Kentaro; et al.
Journal of the Physical Society of Japan, 84(4), p.043202_1 - 043202_4, 2015/04
Times Cited Count：8 Percentile：51.18(Physics, Multidisciplinary)Watanabe, Satoshi; Hashimoto, Kazuyuki; Ishioka, Noriko
JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 102, 2015/03
Watanabe, Satoshi; Hashimoto, Kazuyuki; Ishioka, Noriko
Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1519 - 1521, 2015/02
Times Cited Count：13 Percentile：69.93(Chemistry, Analytical)As basic studies of bifunctional chelating agent for Lu-labeled antibodies, Lu complexation of DOTA and DTPA was investigated by the addition of competing metals, Ca(II), Fe(II) and Zn(II). From comparison of competing metals, the inhibition by competing metals on the Lu complexation was in the order of Ca(II) 
Fe(II) Zn(II) and Ca(II) Zn(II) Fe(II) as DOTA and DTPA, respectively. For comparison between DOTA and DTPA, the susceptibility to the inhibition on Lu complexation by all the three competing metals was DTPA DOTA. Therefore, it was found that DTPA is advantageous for Lu complexation compared with DOTA in the presence of Ca(II), Fe(II) and Zn(II), and that the elimination of Fe from Lu solution is especially effective because the Lu complexation of DTPA is highly inhibited by Fe(II).
Tc for Compton camera imagingHatsukawa, Yuichi; Hashimoto, Kazuyuki; Tsukada, Kazuaki; Sato, Tetsuya; Asai, Masato; Toyoshima, Atsushi; Nagai, Yasuki; Tanimori, Toru*; Sonoda, Shinya*; Kabuki, Shigeto*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1283 - 1285, 2015/02
Times Cited Count：2 Percentile：16.28(Chemistry, Analytical)Technetium-99m (
Tc) is used in radioactive medical diagonostic tests, for example as a radioactive tracer that medical equipment can detect in the human body. It is well suited to the role because it emits readily detectable 141 keV rays, and its half-life is 6.01 hours (meaning that about 94% of it decays to technetium-99 in 24 hours). There are at least 31 commonly used radiopharmaceuticals based on technetium-99m for imaging and functional studies of the brain, myocardium, thyroid, lungs, liver, gallbladder, kidneys, skeleton, blood, and tumors. Recent years, with the develop-ment of the Compton camera which can realize high position resolution, technetium isotopes emitting high energy -rays are required. In this study, technetium-95m which emits some rays around 800 keV was produced by the Mo(p,n)Tc reaction.
Tc from molten MoOKawabata, Masako; Nagai, Yasuki; Hashimoto, Kazuyuki; Saeki, Hideya; Motoishi, Shoji*; Sato, Nozomi*; Ota, Akio*; Shiina, Takayuki*; Kawauchi, Yukimasa*
Journal of the Physical Society of Japan, 84(2), p.023201_1 - 023201_4, 2015/02
Times Cited Count：6 Percentile：43.54(Physics, Multidisciplinary)Tc for medical use can be separated by thermochromatography from a molten MoO sample. Effect of moist oxygen gas on the Tc release from molten MoO samples was investigated using a Mo/Tc generator. Mo was produced with Mo(n,2n)Mo. A new phenomenon has been observed: release rate, separation- and recovery-efficiencies of Tc were higher in the moist oxygen gas than those in the dry oxygen gas. The present result is a significant progress towards the stable production of a high quality Tc from a molten MoO sample with high separation efficiency. The result would also give us a new insight into the interaction between the moist oxygen gas and the molten MoO.
Lu for radioimmunotherapyWatanabe, Satoshi; Hashimoto, Kazuyuki; Watanabe, Shigeki; Iida, Yasuhiko*; Hanaoka, Hirofumi*; Endo, Keigo*; Ishioka, Noriko
Journal of Radioanalytical and Nuclear Chemistry, 303(1), p.935 - 940, 2015/01
Times Cited Count：15 Percentile：74.67(Chemistry, Analytical)Tc from molten MoO samples by repeated milking testsNagai, Yasuki; Kawabata, Masako; Sato, Nozomi; Hashimoto, Kazuyuki; Saeki, Hideya; Motoishi, Shoji*
Journal of the Physical Society of Japan, 83(8), p.083201_1 - 083201_4, 2014/07
Times Cited Count：11 Percentile：58.66(Physics, Multidisciplinary)Lu and 
Re, 
Re using a research reactorHashimoto, Kazuyuki; Fujisaki, Saburo*
Hoshasen To Sangyo, (136), p.17 - 21, 2014/06
no abstracts in English
Nagai, Yasuki; Hashimoto, Kazuyuki
Nihon Butsuri Gakkai-Shi, 69(6), p.370 - 375, 2014/06
In Japan, about 0.9 million diagnostic procedures are carried out using Tc, the daughter nuclide of Mo with a half-life of 66 h, separated from Mo; all Mo radioisotopes are imported. Most of Mo has been produced by the fission reaction of highly enriched U in research reactors in the world. However, a number of incidents of the reactors caused the shortage of Mo worldwide, which triggered widespread discussions on the reliable supply of Mo. We proposed a new route to produce a large quantity of high quality Mo using fast neutrons from an accelerator.
Chiba, Satoshi; Nishio, Katsuhisa; Makii, Hiroyuki; Aritomo, Yoshihiro*; Nishinaka, Ichiro; Ishii, Tetsuro; Tsukada, Kazuaki; Asai, Masato; Furutaka, Kazuyoshi; Hashimoto, Shintaro; et al.
Nuclear Data Sheets, 119, p.229 - 232, 2014/05
Times Cited Count：1 Percentile：0.00(Physics, Nuclear)Watanabe, Satoshi; Hashimoto, Kazuyuki; Ishioka, Noriko
JAEA-Review 2013-059, JAEA Takasaki Annual Report 2012, P. 97, 2014/03
Hashimoto, Kazuyuki; Nagai, Yasuki
Comprehensive Biomedical Physics, Vol.8, p.219 - 227, 2014/00
Radionuclides for medical use are produced in nuclear reactors and in accelerators. The thermal neutron fluxes in nuclear reactors are several orders of magnitude higher than those of other neutron sources, such as accelerator neutrons. Hence, nuclear reactors have been playing important roles in the production of large quantity of medical radionuclides with their half-lives longer than several days. In accelerators, medical radionuclides with their half-lives longer than several minutes are produced. Recent progresses in accelerator technology as well as targetry technology, however, could enable one to obtain high-flux bremsstrahlung and intense energetic accelerator neutrons, and thereby to study new routes to produce medical radionuclides.
